<?php
class Session{

    public static function start(){
        if(!isset($_SESSION)){
            session_start();
            return true;
        }
        return false;
    }
    
    public function has($name){
        self::start();
        if(isset($_SESSION[$name])){
            return true;
        }
        return false;
    }
    
    public function set($name,$value){
        self::start();
        $_SESSION[$name] = $value;
        return $this;
    }
    
    public function get($name){
        self::start();
        if(isset($_SESSION[$name])){
            return $_SESSION[$name];
        }
        return false;
    }
    
    public function kill($name){
        self::start();
        if(isset($_SESSION[$name])){
            unset($_SESSION[$name]);
            return true;
        }
        return false;
    }
}